Propulsion system for continuous mining machine



Jan. 16, 1968 MCLAUGHLIN ET AL 3,363,945

PROPULSION SYSTEM FOR CONTINUOUS MINING MACHINE 3 Sheets-Sheet 1 Filed Aug. 11, 1965 INVENTOR Z n & NW A mm ms P Y m M R c m K M MM AE D SR AF m V. B

Jan. 16, 1968 MQLAUGHLIN ET AL 3,363,945

PROPULSION SYSTEM FOR CONTINUOUS MINING MACHINE Filed Aug. 11, 1965 3 Sheets-Sheet 2 INVENTORZ MC'LAUGHLIN ASA L.

PRIESNITZ ATTORNEYS.

Jan. 16, 1968 v A. MCLAUGHLIN ET AL 3,363,945

PROPULSION SYSTEM FOR CONTINUOUS MINING MACHINE Filed Aug. 11, 1965 3 Sheets-Sheet 3 ASA L. M LAUGHLIN FREDERlCK J. PRIESNITZ United States Patent 3,363,945 PROPULSION SYSTEM FOR CONTINUOUS MINING MACHINE Asa L. McLaughlin and Frederick Priesnitz, Carlsbad, N. More, assignors to Potash Company of America, Carlsbad, N. Mere, a corporation of Colorado Filed Aug. 11, 1965, Ser. No. 478,938 11 Claims. (Cl. 29931) ABSTRACT OF THE DISCLOSURE Propulsion system for continuous mining machine with body movable over mine floor, forward boom with rotary cutting head for swinging across ore face and ore gathering and conveying means including elevated confining portion rearwardly of body, comprising body advancing and retracting mechanism including cooperative driven members spacing body from floor by selective penetration of one of two end-tapered pivots on one said member, one of which always is penetrating floor, and drive means for selectively rotating each cooperative member for moving other pivot forwardly or rearwardly of first to another penetrating position causing first pivot withdrawal from floor by camming action against adjoining floor surfaces.

This invention relates to improvements in mining machines and more particularly to mining machines of the type shown and described in Haworth et al. Patent No. 2,916,274, granted Dec. 8, 1959, and McLaughlin et al. Patent No. 3,052,455, granted Sept. 4, 1962, both owned by the assignee of this application.

Mining machines of the type shown in said patents have been developed for underground mining operations and are particularly effective in potash ore deposits. Such deposits frequently are quite thin in vertical extent and the potash ore usually lies between upper and lower strata of salt (NaCl). The contour of the deposit usually is undulating to some degree requiring that the mining machine be pitched at one time with its forward end elevated and at another time with the forward end declining. Lateral variations also have to be accommodated.

The power requirements for such a machine and the amount of equipment it must carry require a rather substantial length while the height of the ore face requires that the machine have a low head of vertical extent in order to have the required mobility within the confines of the upper and lower strata comprising the mine roof and mine floor. Consequently, propulsion methods which would be satisfactory where head room is not a major factor are not suited for use in a machine meeting such requirements.

It is an object of the present invention to provide a simple, durable and cfiicient propulsion system for a mining machine of the low head type which simplifies operator control of tilt in conjunction with advancing and retracting movements of the machine.

Another object of the invention is to provide a propulsion system having selective advancing and retracting capability which is instantaneously responsive to operator selection and is capable of applying such mobility to a machine of considerable length and weight.

A further object of the invention is to provide a propulsion system for a mining machine of considerable length and weight which imparts a skidding movement to the machine assembly throughout its length, inclusive of swinging or turning movements about a pivotal axis maintained in penetrating relation to the mine floor by the propulsion mechanism.

Other objects reside in novel details of construction and novel combinations and arrangements of parts, all of which will be set forth in the course of the following description.

The practice of our invention will be described with reference to the accompanying drawings illustrating a typical structural embodiment. In the drawings, in the several views of which like parts bear similiar reference numerals:

FIG. 1 is a perspective or isometric view of a mining machine assembly incorporating a preferred embodiment of our invention;

FIG. 2 is a top plan view partially broken to show the arrangement of interior parts of a propulsion system embodying features of our invention;

FIG. 3 is a fragmentary isometric view of the driven members of the assembly shown in FIG. 2;

FIG. 4 is a vertical section through the sub-assembly comprising the driven members shown in FIG. 3 and illustrating the final position in an advance from the righthand side of the view to the lefthand side of the View; and

FIG. 5 is a similar vertical section representing the termination of a retraction movement from the lefthand side of the view to the righthand side of the view.

The machine shown in FIG. 1 comprises a frame or body portion 10 including a forward deck portion 10a and an elevated rear portion 1011. A pair of hydraulic jacks 11 support the forward deck portion and are arranged to impart selective lateral tilt thereto. In addition, the jacks 11 function as the pivotal axis for a pickup conveyor assembly having forward conveyor stretches which turn about the jacks 11 in an action in which they advance toward the mine face along the outside of the machine and return centrally of the machine between the respective jacks l1 and terminate in discharge stretches 12b traveling through an elevated housing 13 which confines the discharge stretches and the ore moved thereby to an elevated discharge point above the end of an ore transport conveyor 14 connected to the rear end of the machine.

The boom member 15 is supported adjacent its forward end from the jacks 11 and has a rotary cutter head 16 at its outer or forward end with a series of cutter bits 17 disposed on the head 16 in a special arrangement which permits the cutter to effectively remove ore from an ore face when swinging either to right or left with the same direction of rotation applied to the head. A guard member 18 is disposed directly behind the head 16 to confine the fall of loosened ore so as to distribute it within the moving pattern of the pickup conveyor assembly 12. The motor for the cutter drive is shown at 19 and a gear box or speed reducer assembly 20 is utilized to control the rate of rotation of cutter head 16.

Lengthwise movement of body 10 toward or away from the ore face is made relative to a pivotal axis 21 at the rear of the machine and any lateral swinging movement of the front of the machine, as in directing the cutter head in a sweep across the ore face, develops an arcuate path about the single pivot point 21 which continues until the propulsion mechanism is again actuated to establish a new pivot point position as will be explained in detail hereinafter. The drive or propulsion assembly is shown at 22 and the transmission system for assembly 22 is located within a housing 23. The motor for driving conveyor assembly 12 is shown at 24.

The lateral movement of the forward end of the machine is provided by an assembly including a pair of wedging jacks 26, each pivotally mounted on a skid or platform member 27 having a flat bottom. A working jack 28 has one end secured to rear body portion 10b and its opposite end in pivotal connection with the housing for the base of jack 26 seated on platform member 27. The jacks 26 are selectively elevated to an upright position in wedging engagement with the mine roof by operation of working jacks 28 and 28a and a hydraulic drive unit 29 in pivotal connection with the forward deck portion a has a universal joint connection with platform member 27 as shown at 311.

A pan-like member 32 supporting the machine operators seat 33 is connected to one platform member by a suitable connector 34 and is drawn with platform member 27 in its various movements. A control panel 35 is secured on member 32 forwardly of seat 33 and the operator directs the various actions of the machine from said platform while having the operating parts in his range of vision. The switch housing containing electric components of the machine is at the rear as shown at 36 and preferably is mounted on rear body portion 1%.

After one of the jacks 26 is brought into wedging engagement with the mine roof, the hydraulic drive unit 29 is actuated to pull against the universal joint connection 31 on platform 27 and thus drag the forward end of the machine laterally along an arcuate path having pivot position 21 as its center point. It will be understood that the length of the jacks 26 is in excess of the height of the mine room in which the machine is operating and when the top of the jack is raised into wedging engagement with the roof, the jack is tilted upwardly toward the machine. Pull exerted against the lower end of jack 26 increases the wedging engagement and holds it securely while the machine is being pulled toward such post.

As previously mentioned herein, the apparatus shown in FIG. 1 utilizes a novel propulsion system which provides advance and retraction of the machine in conjunction with, or prior to lateral swinging movement of the forward end of the machine and the boom, as in cutter attack for removal of ore from an ore face. A preferred propulsion system or drive assembly is shown in FIGS. 2 through 5, the structural arrangement of which and the functioning now will be described.

An upper driven member 49a and a lower driven member 40b are disposed in superposed concentric arrangement about a post 41 extending into a central recess 42 of a covering plate member 43 supported by the elevated rear portion 10b of the body of the machine. The lower member 4% has a pair of recesses 44 spaced 180 about its central axis and pivot pins 45 having vertically extending keyways 46 end-tapered lower ends are movable vertically in the recesses but are held against separation from member 4% by key members 47, preferably set screws.

The members 4611 and 441117 have peripheral surfaces 48a and 481), respectively, formed as sprockets or gears. A motor and speed reducer assembly 49 drives a chain 50 engaging a sprocket 51 carrying another chain 52 engaging sprocket 48a and a similar motor and speed reducer assembly 53 drives another chain 54 mounted on another sprocket 55 carrying a chain 56 engaging sprocket 48b, permitting selective and independent rotation of members 40a and 40b about the concentric axis defined by post 41.

One of the features of the dual-rotation propulsion system illustrated in FIGS. 2 through 5 is that whenever the lower member 4% is rotated 180, such rotation will cause a disengaged pivot pin 45 to penetrate the mine floor and establish a new pivot point position 21 with depressed surfaces of the floor in contact with the tapered end surfaces of pin 45, as shown in FIGS. 4 and 5, while the other pin 45 is caused to retract from its previous floor penetrating position by a camming movement of its tapered surface against adjoining surfaces of the floor and function as an idler until the system is actuated again to establish a new pivot position. Direction is controlled by selective rotation of the upper member 40a to provide a lateral shifting of the single pivot established at a new setting. The structural features producing this action are shown in FIGS. 3, 4 and 5.

As shown in FIG. 3, member 40b is cylindrical and has a central recess 60 and the vertical recesses 44 previously described. It is of somewhat larger diameter than member 49a which rotates on its flat top surface. Post 41 preferably is a sectional assembly (FIGS. 4 and 5) interconnected by a plurality of screws 61 extending through the bottom portion 41a into the upper portion 41b. The bottom portion has a lower flange 41x which supports a bushing 62 and the bottom surface of member 40b. Member 40a is segmental rather than completely cylindrical and covers approximately 200 of the total 360 top surface of member 4%. The undersurface of member 40a adjacent the terminal edge is undercut in a helical pattern at 63, including a lateral inclination downwardly toward the periphery of the member.

The top or head 45a of the pivot pins 45 inclines from a central portion to the periphery in a downward direction but instead of being a conical shape, the portion nearest keyway 46 is pitched at a less acute angle than the portion nearest post 41. This arrangement permits a horizontal undersurface of member 40a to force the top 45a of one pin 45 to the level of the top surface of member 40b causing the pin to penetrate the mine fioor to establish the pivot point position 21. At 180 from the point of pressing contact which is the location of the other pin 45, the overhang of member 40a has terminated and that pin elevates from a former penetration position as previously described and rests lightly on the surface of the mine floor.

FIG. 4 represents a position in the operation of the propulsion mechanism in which the righthand pin 45 has just been caused to penetrate the mine floor 64 and establish a new pivot point position 21, while the other pin 45 has been allowed to elevate and is resting lightly on the mine floor. FIG. 5 represents another rotational position in which the lefthand pin is held in floor Penetrating position and the righthand pin has retracted from the floor.

In a commercial machine of the type illustrated in FIG. 1, the linear distance between the pins 45 may be on the order of two feet, in which case the 180 rotation will produce an advance or retraction of two feet. When a lesser degree of movement is desired, a rotation of less than 180 will provide the requisite advance or retraction.

We claim:

1. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward ore-discharging stretches, means confining the ore-discharging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including cooperative driven members mounted on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on one of said members, and means for moving the other pivot pin forwardly or rearwardly of the floor-penetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor.

2. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body including forward ore-gathering stretches and rearward ore-discharging stretches, means confining the oredischarging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including cooperative driven members mounted on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on one of said members, and means for rotating the other pivot pin forwardly or rearwardly of the floor-penetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor.

3. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward ore-discharging stretches, means confining the oredischarging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including cooperative driven members mounted for independent rotation on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on one of said members, and means for rotating the other pivot pin forwardly or rearwardly of the floor-penetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adoining surfaces of the floor.

4. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward oredischarging stretches, means confining the ore-discharging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including concentric cooperative driven members mounted for independent rotation on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on one of said members, and means for rotating the other pivot pin forwardly or rearwardly of the floor-penetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor.

5. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward ore-discharging stretches, means confining the oredischarging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including superposed driven members mounted for rotation in con-centric arrangement on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on the lower of said members, means for rotating the lower member to rotate the other pivot pin forwardly or rearwardly of the floorpenetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor, and cam means on the upper of said members for selectively forcing one of said pins to penetrate the mine floor.

6. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward oredischarging stretches, means confining the oredischarging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection there with for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including superposed driven members mounted for rotation in concentric arrangement on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on the lower of said members, means for rotating the lower member to rotate the other pivot pin forwardly or rearwardly of the floorpenetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor, and cam means on the upper of said members for selectively forcing one of said pins to penetrate the mine floor and providing clearance for the other pin so as to permit its retraction from the mine floor.

7. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward oredischarging stretches, means confining the ore-discharging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including cooperative driven members mounted on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on one of said members, means for rotating the pin-carrying member so as to move the other pivot pin forwardly or rearwardly of the floor-penetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor.

8. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward ore-discharging stretches, means confining the ore-discharging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including cooperative driven members mounted on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on one of said members, means for rotating the pin-carrying member so as to move the other pivot pin forwardly or rearwardly of the floorpenetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor, and means for rotating the other driven member.

9. In a mining machine having a body portion for movement over a mine floor, a boom at the forward end of the body having a rotary cutter head for acting on an ore face during swinging movements of the boom, an ore pickup conveyor assembly supported on the body, including forward ore-gathering stretches and rearward ore-discharging stretches, means confining the ore-discharging stretches and ore moved thereby to an elevated point of discharge rearwardly of the body, and means laterally of the body in driving connection therewith for swinging the forward end of the body about a single pivotal axis at the rear of the body while the cutter head is acting on the ore face, the improvement which comprises means for advancing and retracting the body relative to the ore face, including superposed driven members mounted for rotation about a common axis on the rear of the body and supported in spaced relation to the mine floor by selective floor-penetration of one of two end-tapered pivot pins carried on the lower of said members, means for rotating the pin-carrying member so as to move the other pivot pin forwardly or rearwardly of the floor-penetrating pin to a position where said other pin penetrates the mine floor and the first pin is withdrawn from penetration by a camming movement of its tapered surface against adjoining surfaces of the floor, and independently actuated means for rotating the upper superposed member.

16. A propulsion system for a mining machine having a plurality of floor-contacting supports connected to a body portion of the machine and selectively slidable on the mine floor to position portions of the mining machine in different operating positions, comprising two driven members in superposed relation secured on an extended portion of the body acting as a common pivotal axis for said members, each said member having a peripheral portion formed as a gear, a pair of vertically disposed pivots having tapered lower ends, each supported on the lower member at opposite sides of its central axis, each said member arranged for limited vertical movement to dispose the top of the pivot above the top surface of the lower member when the pivot is not penetrating the mine floor, the upper member having a cam surface disposed for engagement with the top surface of said pivot pins for forcing the tapered end of the pin to penetrate the mine floor during such engagement as a single pivot about which the machine advances and retracts, and the cam surface being of such length that it will not engage both pins at the same time, a prime mover for each superposed member, and transmission members connecting each superposed member with its prime mover, whereby rotating the lower member about 180 will force one pivot pin to penetrate the mine floor and permit retraction of the other by a camming movement of its tapered surface against adjoining surfaces of the floor and thereby advance or retract the machine relative to an ore face in the mine.

11. A propulsion system for a mining machine having a plurality of floor-contacting supports connected to a body portion of the machine and selectively slidable on the mine floor to position portions of the mining machine in different operating positions, comprising two driven members in superposed relation secured on an extended portion of the body acting as a common pivotal axis for said members, each said member having a peripheral portion formed as a gear, a pair of vertically disposed pivots having tapered lower ends, each supported on the lower member at opposite sides of its central axis, each said member arranged for limited vertical movement to dispose the top of the pivot above the top surface of the lower member when the pivot is not penetrating the mine floor, the upper member having a cam surface disposed for engagement with the top surface of said pivot pins for forcing the tapered end of the pin to penetrate the mine floor during such engagement as a single pivot about which the machine advances and retracts, and the cam surface being of such length that it will not engage both pins at the same time, a prime mover for each superposed member, transmission members connecting each superposed member with its prime mover, and means for initiating rotation of the lower superposed member to advance and retract the machine and for selectively rotating the upper superposed member to provide a lateral shifting of the single pivot point established at a new setting so as to control the direction of the machine.

References Cited UNITED STATES PATENTS 2,916,274 12/1959 Haworth et al 299-31 3,255,836 6/1966 Hoppmann et al 180-8 ERNEST R. PURSER, Primary Examiner. 

